@import url('https://fonts.googleapis.com/css?family=Montserrat:400,600&display=swap');

* {
    box-sizing: border-box;
}

:root {
    --border-color: #144fc6;
    --fill-color: #6ab3f8;
}

body {
    background-color: #3494e4;
    color: #fff;
    font-family: 'Montserrat', sans-serif;
    display: flex;
    flex-direction: column;
    align-items: center;
}

h1,
h4 {
    margin: 10px;
}

.cup {
    width: 150px;
    height: 320px;
    background-color: #fff;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    border: 4px solid var(--border-color);
    border-radius: 0 0 40px 40px;
    -webkit-border-radius: 0 0 40px 40px;
    -moz-border-radius: 0 0 40px 40px;
    -ms-border-radius: 0 0 40px 40px;
    -o-border-radius: 0 0 40px 40px;
}

.remained {
    height: 100%;
    background-color: #fff;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    color: var(--border-color);
    transition: 0.5s linear;
    -webkit-transition: 0.5s linear;
    -moz-transition: 0.5s linear;
    -ms-transition: 0.5s linear;
    -o-transition: 0.5s linear;
}

.remained #liters {
    font-size: 18px;
    font-weight: bold;
}

.percentage {
    background-color: var(--fill-color);
    color: var(--border-color);
    font-weight: bold;
    font-size: 30px;
    height: 0%;
    display: flex;
    justify-content: center;
    align-items: center;
    transition: 0.5s linear;
    -webkit-transition: 0.5s linear;
    -moz-transition: 0.5s linear;
    -ms-transition: 0.5s linear;
    -o-transition: 0.5s linear;
}

.cups {
    width: 300px;
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    align-items: center;

}

.cups .cup-small {
    margin: 10px;
    width: 50px;
    height: 100px;
    background-color: rgba(255, 255, 255, 0.9);
    color: #144fc6;
    text-align: center;
    cursor: pointer;
    padding-top: 30px;
    border-radius: 0 0 20px 20px;
    -webkit-border-radius: 0 0 20px 20px;
    -moz-border-radius: 0 0 20px 20px;
    -ms-border-radius: 0 0 20px 20px;
    -o-border-radius: 0 0 20px 20px;
    transition: all 0.5s ease-in-out;
    -webkit-transition: all 0.5s ease-in-out;
    -moz-transition: all 0.5s ease-in-out;
    -ms-transition: all 0.5s ease-in-out;
    -o-transition: all 0.5s ease-in-out;
}

.cups .cup-small.cup-small-active {
    background-color: var(--fill-color);
    color: #fff;
}